To my knowledge, the gas tank in the 2310 has not moved in recents times. However in the 2320, Parker moved the gas tank forward in 2004 about 18 inches or so and added a 14 x 24 deck hatch over the bilge directly in front of the transom. The tank now begins just below the forward edge of the new deck hatch and runs up to the PH door which is as far forward as it can go. In 2004, the dual batteries were also move about 2 feet further forward onto a raised platform in the bilge.
Ronnie's boat is a 2003 2320. He has no transom deck hatch, as the tank begins where the transom box meets the deck and stops short of the PH door. He has a deck hatch in front of the PH door. The batteries are on the deck as far aft as possible in the transom box port and stbd.
Weight is weight, and CG (center of gravity) is CG. Boaters need to grasp the concept of weight and balance and how it affects CG and handling. It does not matter what type of craft it is. It is simply physics at work. I have more than 3000 flight hours in various military aircraft and rode ships for more than 15 years. So, I do have a little experience in this area. Ronnie and I have spoken at length as to how he can redistribute the weight in his boat so that the weight and balance would be essentially equal to the redisign in 2004. Again, weight is weight whether it be gas or batteries. Move one or the other, the boat knows no difference.
As far as Bahadude's 2310 and his assertion that Parkers are heavy in the rear; actually the Parker 2310 as well as the 2320 are very well balanced boats. The 2310 has a nice fiberglass cabin forward (ambient weight). The aluminum gas tank doesn't weigh much nor does that beautiful west coast livewell which was added. The aluminum Armstrong bracket with integrated flotation chamber doesn't weigh much, in fact it floats.
Now lets talk about the weight and balance. The four stroke engine is a little heavier but then there is the flotation chamber of the bracket. Although not much weight, subtract the weight of an oil tank/oil etc. associated w/ a 2 stroke. Now lets look at the gas tank post 2004. Standard aluminum tank positioned w/ aprrox 1/3 forward of CG, and 2/3 aft of CG. Above deck, the cockpit is essential bare (no extra weight porportional to the rest of the deck layout..the 3/4 marine plywood runs the length of the boat).
Lets relate these features to any other comparable boat. I'd say pretty much the same except the Parker is overbuilt (heavier (stern to bow) than the average hull).. a good thing. The gas tank (post 2004) in the Parker is essentially located in the same position relative to CG as most boats. However, this is where knowledge of weight and balance is important. Parker gas tanks are huge relative to the displacement of the hull. If YOU as a boat owner choose to run heavy and carry a lot weight in the tank (gas is 6.8-7 lb per gallon) one would assume that more than likely you are going on a long trip with a lot of gear and possibly lots of people, of which most would be loaded forward of CG to offset the weight of the gas. If not, then you have limited your boats handling capabilities by improperly loading the boat. Also, adjust the livewell to hold just enough water for the amount of bait.
As far as other factors you can adjust, use a nice heavy anchor with plenty of chain if you have a windlass. A 200 4 stroke is not enough power for a DV 23 Parker. A 250 is minimum. Check your cavitiation plate while running at cruise speed. Should be just below the surface or at the surface. Raise you motor accordingly. IF ENGINE ON A BRACKET, DO NOT USE A BOW LIFTING PROP, such a yamaha saltwater series or Mirage Plus. Use a 4 blade Mercury Rev 4 stern lifting prop.
Out of time, got to go.
jim
to the bow. 
